Note: Descriptions are shown in the official language in which they were submitted.
INFORMATION DISPLAY SCHEME FOR
SUBSCRIBERS OF A SUBSCRIPTION TELEVISION SYSTEM
BACKGROUNI) OF THE INVENTION
The present invention relates generally to the field of subscri~
tion communication systems and, more particularly, is directed to ~n
information display scheme which simplifies the display of information
to subscribers of a subscription communication system.
Subscription communications systems, such as television and spe-
cial events programing, have gained wide spread acceptance as an
efficient way of providing a vast selection of information and
entertainment programming to the public. Such systems normally
charge a fixed monthly service îee which entitles the subscriber to
receive regular programming for the entire month. Many systems also
provide R "movie channel" or a "special events channel" for an addi-
tional fee. Though a subscriber may wish to view only one or two
movies or special events during the course of a month, he must
nevertheless pay the full additional fee. Psyment of a full fee where
only a fraction of the service is utilized is uneconomical and often
results in a majority of subscribers signing up to receive only regulhr
programming. Thus other services are not sufficiently supported to
provide quality programming.
A subscription television system should include provisions for a
subscriber not only to select which channels he wishes to receive, but
also to select which programs on 8 particular ch~nnel he wishes to
view. In order to achieve maximum flexibility, the subscriber should
also be permitted to make this selection at anytime without having to
indicate to the broadcastor or system operator beforehand that he
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wishes to view a particular program. Ideally, the system should make
all programming available to the subscriber and perm~t him to select
and pay for only those programs that he actually views. This concept
is often called ?'pay-per-program".
In a subscription television system h~ving a p~y-per-program fe~-
ture, the system operator must be continuously informed of the pro-
gra ms selec ted for viewing by the subscriber for proper billing. Thus,
such systems require an up-link or some form of communication from
the subscriber to the system operator. Subscribers could, of course,
maintain a log of all programs viewed and periodically send the log to
the system operator for billing purposes. The integrity of such a bill-
ing procedure is suspect, however, and is impractical for a system
hsving many subscribers. On-line feedbsck to the system operator of
programs selected for viewing by the subscriber is also possible but
such feedback provisions greatly ccmplicate and increase the cost of
the system.
In subscription television systems having a pay-per-program fea-
ture, the subscriber must slso be kept apprised of his account status.
Such information could be provided by a conventional teletext system
where all the digital pulses which represent data are tr&nsmitted from
the headend of the system on lines of the vertical blanking interval of
the television signals. This data represents alphanumeric and graphical
information wh}ch may be selectively displayed to the subscriber using
a television receiver adapted for teletext reception. Typically, the
subscriber requests a partieular magazine page of information for
display using ~ re mote keypad interfaced to the teletext receiver. The
receiver waits until the requested page is transmitted in the channel
then captures the information in a page storage buffer. The contents
of the buffer are displayed through A character generator onto the tel-
evision screen.
In teletext systems known in the prior art, no significsnt
modifications are made to the transmitted pages prior to their display
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on the screen other than, perhaps, the addition of a
page number in a fixed position on certain pages. In
particular, conventional teletext systems do not provide
for the addition of locally generated information by
the receiver which might change the meaning or the
interpretation of the transmitted information. Thus,
information that is specifically directed to a
particular subscriber, for example billing information,
must always be completely generated at the headend or
distributor end for down loading ~o the subscriber.
This adds to the complexity of the system. Thus, in
systems having a pay-per-program feature, means must
still be provided for communicating to the system
operator a listing of programs watched by the
subscriber. Such a requirement further increases the
complexity and cost of the system.
SUMMARY OF THE INVENTION
It is an object of an aspect of the present
invention to provide an information display scheme which
simplifies the display of information to subscribers of
a subscription communication system.
It is an object of an aspect of the present
invention to provide an information display scheme for
subscribers of a subscription communication system which
uses a template page transmitted from the headend of the
system as a format for the display of locally generated
information.
It is an object of an aspect of the present
invention to proYide an information display scheme for
subscribers of a subscription communication system which
uses a template page transmitted from the headend of the
system as a format for the display of locally generated
customer unique information such as a billing summary at
the subscriber's receiver.
It is an object of an aspect of the present
invention to provide an information display scheme for
subscribers of a subscription communication system which
uses a template page transmitted from the headend of the
system as a format for the display of parameters
associated with the status of the system.
It is an object of an aspect of the present
invention to provide an improved billing system for a
subscription communication system which permits the
subscriber to select and pay for only those programs
that the subscriber actually views.
It is an object of an aspect of the present
inven~ion to provide an improved billing system for a
subscription communication system which permits the
subscriber to select and pay for programs the subscriber
wishes to view without having to communicate beforehand
with the system operator.
It is an object of an aspect of the present
invention to provide an improved billing system for a
subscription communication system which permits the
subscriber to obtain on demand a summary of the
subscriber's billing account information.
It is an object of an aspect of the present
invention to provide an information display scheme for
subscribers of a subscription communication system which
uses a template page transmitted from the headend of the
system as a format for the display of locally generated
information, the same template page being used for many
subscribers.
Various aspects of the invention are as follows:
An information display system for displaying
subscriber unique information to subscribers of a
subscription communications system, the information
display system comprising:
display means coupled to the communications system
for displaying information received from the communica-
tions system;
template page receiving means coupled to the
communications system for receiving a template page as a
format for the subscriber unique information;
storage means coupled to the template page
receiving means for storing the template page;
logic means coupled to the communications system,
the display means and to the storage means for locally
generating and maintaining at least some of the
subscriber unique information, said logic means
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combining the subscriber unique information with the
template page for display on said displays means.
In a subscription television system having means
for transmitting a scrambled video signal representing
television programs to a descrambling decoder and
television receiving means for receiving a descrambled
signal from the decoder, an information display system
for displaying subscriber unique information on said
television receiving means, said display system
comprising:
template page receiving means coupled to said
decoder for receiving a template page as a format for
the subscriber unique information;
storage means coupled to said template page
receiving means for the storing to said template page;
logic means coupled to the decoder and to said
storage means for generating at least some of the
subscriber unique information, said logic means
combining the subscriber unique information with said
template page for display on said television receiving
means.
A method of displaying subscriber unique
information to subscribers of a subscription
communications system, the method comprising the steps
of:
locally generating at least some of the subscriber
unique information;
providing a template page from the communications
system as a format for the subscriber unique
information;
temporarily storing said template page; and
combining the s~lbscriber unique information with
said template page for display to the subscriber.
By way of added explanation, the present invention
has particular application in subscription television
systems which transmit television programs in the form
of scrambled signals to a decoder in the subscriber's
home. A secure microprocessor within the decoder
determines which signals are unscrambled for viewing
dependent on the prcgram selected by the subscriber and
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the status of the subscriber's account maintained by the
microprocessor. The microprocessor is loaded with
account data from the headend of the system which
reflects service fees pre-paid by the subscriber. The
cost of programs selected for viewing are automatically
subtracted from the subscriber's account balance
maintained by the microprocessor. Where the balance is
insufficient to cover the cost of the program or exceeds
an authorized credit limit, the microprocessor prevents
the program from being descranbled. The subscriber's
account balance may be increased by the subscriber
sending to the system operator additional pre-paid
service fees.
The billing acco~nt information maintained by the
microprocessor is readily available for display to the
subscriber and may be combined with a template page
transmitted from the headend of the system over a
convenient channel as a report format. For example, the
template page may consist of nothing more than column
headings for a billing summary.
Further objects, features and other aspects of the
present invention will be understood from the detailed
description of the preferred embodiment of the
invention with reference to the annexed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a block diagram of a subscription
television decoder with a secure microprocessor in
accordance with the present invention.
Figure 2 is a block diagram of a template page
scheme as a format for displaying locally generated
information in accordance with the present invention.
Figures 3, 4 and 5 are examples of displays of
locally generated information on a template page in
accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to Figure 1, a block diagram is
provided showing one example of a decoder for a
subscription television system which includes a
microprocessor for controlling the operation of the
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decoder as well as maintaining the subscriber's billing
information.
As shown in Figure 1, the MAC television signal
first enters the multiplexer 300, which separates from
it the luminance and chrominance signals as well as the
audio, synchronization, timing and teletext
information. The luminance signal is delivered to
luminance
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store 302, a CCD line store, where it is decompressed, and then to
low-pass filter 304, where it is filtereù. The analog luminance signal
then goes to output interface 306. The ssmpling signals necessary to
decompress luminflnce ~re produced in timing generator 308 and
supplied to luminance store 302 by two clock drivers 310.
The chrominan~ce signal from demultiplexer 300 is also decom-
pressed in chrominance store 312, which is also a CCD line storer
Separate outputs are provided for the two color difference signals,
which ~re filtered in two low-p~ss filters 314 ~nd then supplied to
output interface 306. The necessary sampling signals are supplied to
chrominance store 312 from timing generator 308 through three clock
drivers 310.
Signals not constituting luminance or chrominflnce are also
separated from the MAC television signal by demultiplexer 300. These
signals include audio, teletext and sychronization and timing informa-
tion. Audio, teletext, and synchronization signals are delivered to
demultiplexer 316 through one of two low-pass filters 318; while the
fixed-frequency timing information is delivered to demultiplexer 316
through band-pass filter 320. Demultiplexer 316 separates these
signals, supplying the audio to audio demultiplexer 322 and the synchro-
nization and timing signals to clock and synchronization recovery cir-
cuit 324 and timing generator 308. Audio information from
demultiplexer 316 is separated into four channels in audio demultiplexer
322 and output by analog audio processor 326. Teletext information is
sent to character generator 328 via clock and synchronization recovery
circuity 324. Decoder operstions are under the control of
microprocessor 330, which communicates with clock and synchronization
recovery circuit 324, teletext character generator 328, And RAM 332
over bidirect~onal buses 334, 336, snd 338.
Output interface 306 receives teletext characters from chsracter
generator 326, luminance from low-pass filter 304, chrominance from
IOW-PASS filters 314, and timing signals from timing gener~tor 308. Its
output is a standard NTSC color television signal.
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Figure 2 is a block diagram of the template page scheme in
accordance with the present invention. As shown, microprocessor 360
can be used to replace micrprocessor 330 shown in Figure 1 to also
control the operations of a decoder. E~lock 350 of Figure 2 is a da ta
recovery unit which recovers information data and template page data
from a data channel in the decoder, flS for example the decoder shown
in Figure l. The recovered data from data recovery unit 350 is
supplied to page selection unit 351 which selects data for storage in
p~ge buffer 352. Microprocessor 360 is coupled to p~ge selection
unit 351 and page buffer 352 to also control the selection of data for
storage in page buffer 352. Keypad interface 354 is ~oupled to
microprocessor 360 for interfflcing a keypad, or Gther device operable
by the subscriber, to control the operation of the microprocessor and
to indicate to the microprocessor such information as which progra ms
the subscriber wishes to view. Microprocessor 360 is also coupled to
character generator 328, also shown in Figure l, which processes
infromation from page buffer 352 and microprocessor 360 for display
on the television screen via output interface 306 shown in Figure 1 as
well. Output interface 306 may be controlled to select for output to
the television screen normal television video signals or textual video
signals from character generator 328.
In a subscription television system having a pay-per-program fea-
ture in accordance with the present invention, the subscriber mails in
to, or otherwise deposits with, the operator of the system an emount
of money equal to the fixed monthly service fee plus an additional
amount to be held in reserve for the subscriber which he may draw
agaînst to view special programs not included in regular programming
under the fixed monthly fee. The operator then transmits signals over
the channel to the particular subscriber which indicates how much
money was received from the subscriber. This information is stored in
secure microprocessor 360. Microprocessor 360 includes account bal-
ance means for maintaining the subscriber's sccount bslance which is
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updated by the payment information received from the system operator.
The microprocessor also includes means for determining the cost of
programs available for viewing by the subscriber.
This cost information may also be transmitted by the system
operator to the microprocessor and stored therein.
The cost of programs selected for viewing by the subscriber are
automatically subtracted from the subscriber's balance rnaintained by
the microprocessor. When the belance is insufficient to cover the cost
of the program, or exceeds ~ predetermined credit limit, the
microprocessor prevents the program transmitted over the channel from
being descrambled. Microprocessor 360 also sets an internal flag
associated with each program selected for viewing. The subscriber's
account balance may be increased by the subscriber pre-pflying addi-
tional service fees.
Figures 4-5 illustrete various reports or page displays that the
subscriber may command microprocessor 360 via keypfid interfsce 354
to display on the television screen. Figure 4 illustrates a display
showing the subscriber's billing account status. In this example, the
display comprises Part A enclosed in a box and Part B. The box is
drawn around Part A to set it apart frorn Part B for purposes of
explanation. Note that the information contained in Part 13 is descrip-
tive information or headings and is the same for each subscriber.
Part B thus serves as Q template or heading for the information
unique to each subscriber contained in Part A. Since Part B is the
same for many subscribers, it mfiy be efficiently transmitted over a
teletext or other channel in the system to these subscribers at the
same tlme. The information contained in Part A on the other hand,
is unique to each subscriber and m&y be more efficiently generated
and maintained by microprocessor 360 coupled to the decoder in each
subscriber's home.
Figure 5 illustrates a display showing a system control page indi-
cating the status of various parameters associated with the decoder.
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Here sgain, the display is divided into Parts A and B for purposes of
explanation. As described above with respect to Figure ~, Part B, is
descriptive information serving as a template or format for the infor-
Mation contained in Psrt A and is the same for many subscribers.
The information in Part A is provided by microprocessor 360.
Figure 5 is a further exa mple of a display in accord~nce with
the present invention similarly divided into Parts A and B as above
described. This display lists the number of special programs viewed
and their costs. In order to generate this display, the templflte page
includes a listing of all programs made evailable to the subscriber and
their costs. As the list is received by microprocessor 360, it
determines which programs do not have a corresponding internal flag
set indicating that those programs were not selected for viewing by
the subscriber. The cost figure for these programs is overprinted in
the display with "~*~*" indicating that the programs were not pur-
chased.
As Figures 4-5 illustrate, the information display system in
accordance with the present invention effectively utilizes a template or
format scheme to display information not unique to a specific sub-
scriber. Because this type of information is the sa me for many sub-
scribers, rather than being generated locally for each subscriber, it can
be transmitted to everyone at the same time from the main
distribution point for the system. The information that is unique to
each subscriber, however, is more efficiently generated and maintained
by the microprocessor coupled to the decoder in each subscriber's
home. Thus, the present invention avoids having to send subscriber
unique inform~tion from the headend of the system for eflch subscriber.
In a large system, e.g., in a system using a satellite to reach millions
of subscribers, the benefits of not having to provide from the headend
all subscriber unique information are substsntial.
The information display system of the present invention
overcomes the above noted difficiencies in subscription television
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systems known in the prior flrt which have a pay-pe--program feature.
In conventional systems, it is necessary that an up link, e.g., by tele-
phone, or some other form of feedback communication be provided
from the subscriber to the system operator so that the subscriber is
correctly billed for the programs viewed. In the system of the
present invention, no feedback to the system operator of any kind is
required. The system always operates in a download mode. Thus, the
system is less complicated and easier to maintain. Moreover, because
the microprocessor coupled to the decoder in the subscriber's home
does all of the housekeeping functions with respect to which progrRms
are selected for viewing and automatically subtracts the cost of the
programs from the subscriber's account balance, the system is less
burdened and can be more fully utilized to provide additional pro-
gramming. The system of the present invention also permits the sta-
tus of the decoder to be continuously monitored and displayed to the
subscriber.
The present invention has been described in detail in connection
with a preferred embodiment. The embodiment, however, is merely an
example and the invention is not restricted thereto. It will be under-
stood by those skilled in the art ~rom a reading of the specification
that vflriations and modifications can be made within the scope of the
present invention as defined by the appended claims.
